1. Field of the Invention
The field of the invention is alarm clocks.
2. Prior Art
The instant invention is an alarm clock having two modes of operation; namely, a virtually silent mode and an audible mode.
Alarm clocks having only an audible alarm mode are well known.
Similarly, alarm clocks having a vibratory (or silent) mode have been known for some time. An example of such a clock is described in United Kingdom Patent No. 2,205,665 issued to Michael J. Dines. The Dines Vibratory Alarm Clock is a portable electronic clock having the shape of a flattened cube with rounded corners, with its front side extending lower than the backside. The purpose of the comparatively small depth of the clock (as compared to its other dimensions) and for the front extending lower than the back is to allow for the clock to be placed under a pillow more comfortably for the user. The controls of the Dines Clock are on the face and include a 3-detent switch with a time set position, an alarm set position, and a lock position, another 3-detent switch having an alarm off position, an alarm on position, and a snooze position. The Dines Clock also has on its face hour and minute setting buttons for setting the current time and the time for the alarm to go off when the first of the above-described switches is set in the time set and alarm set positions, respectively, and a large alarm stop button to stop the alarm once alarm has started. The face of the Dines Clock also has an LCD display for visual display of the current time and the time for which the alarm is set, including an indication of whether snooze has been chosen. On the face of the clock there is a button used for turning on a light to illuminate the LCD display. The Dines Clock also has a face plate hingedly attached to the front of the clock to protect the controls on the face of the clock.
Within the housing of the Dines Clock is a generally conventional electronic clock mechanism including an alarm signal generating circuit. This electronic clock mechanism and the LCD display combine together to display time or alarm time as is well known in the art, and the clock is set according to conventional methods. The clock circuitry is powered by a 1.5 volt battery, such as the LR44 battery manufactured by Toshiba, which battery is mounted in the housing.
In the Dines Clock the alarm pulse from the clock circuit triggers the opening of a second circuit which includes a pulsing circuit and a motor. This separate circuit is powered by a separate battery power supply, typically two AA size 1.5 volt batteries such as manufactured by Eveready Battery Company, Inc. Thus, the motor is turned on in a pulsating fashion by the alarm pulse from the clock's circuitry. Where as most motors are typically mounted symmetrically to a cam in the Dines Clock the motor driveshaft is mounted eccentrically to a cam so that when the motor is operated substantial vibrations are imparted to the housing of the clock to which the motor is physically mounted.
Clocks such as the Dines Clock are particularly adapted for use by the deaf who cannot hear normal audible alarms and is also adaptable for the use when more than one person sleeping in a room and one must be woken up much earlier than the other.
The Dines Clock is also adapted for use in other environments where a normal alarm would not be heard (for example, in noisy environments) or in a situation where a normal alarm would not be appropriate. For such purposes, the clock may be clipped to the clothing of the user or may be kept in the user's pocket.
Other prior silent alarms includes the alarm clock shown in U.S. Pat. No. 4,028,882 issued to Hrand Muncheryan which features a silent alarm having a resonator unit disposed a substantial distance away from the clock and connected thereto by conventional wiring. This, of course, is not convenient for travel and provides quite a bit of awkwardness for a sleeper who might get tangled in the wiring. U.S. Pat. Nos. 4,093,944 and 4,180,810 both also issued to Muncheryan illustrate variations on the same theme.
A recently issued patent, U.S. Pat. No. 4,920,525, issued to Jack B. Meister, also features an alarm clock having a silent alarm. The Meister Clock has its clock circuitry, clock battery source, and operator panel all contained in a separate module separate from the clock's housing. The clock module of Meister includes an operator panel positioned adjacent to the display and having time setting switches mounted thereon, hinged flap for removably covering the panel while permitting viewing of the display, whereby the clock module may be in placed as a pocket watch separate from the quiet alarm.